1. Field Of The Invention
This invention is directed to a cleaning apparatus for cleaning a surface and, in one aspect, to such an apparatus for cleaning a viewing surface or window or optical fiber end such as those used in object and product sorters.
2. Description Of Related Art
Product sorters for sorting objects such as diamonds, peanuts, coffee beans, and grains are old and well known. Many of these sorters employ a viewing surface, a window or a surface of an optical fiber end past or through which pass the objects to be sorted. The surface or window is part of a viewing device which views light reflected from each object.
A typical sorter using a plurality of light sources and optical viewing means is shown in U.S. Pat. No. 3,914,601. A typical sorter using light conducting rods is shown in U.S. Pat. No. 4,057,146.
Often there is foreign material, debris, or dust which is intermingled with the objects to be sorted. Some of this unwanted material can remain on the viewing surface or rod ends, inhibiting viewing and resulting in false signals from the viewing apparatus. Prior art efforts to clean the viewing surfaces, windows or fiber ends have included the disposition of air nozzles immovably fixed above a window to provide blasts of compressed air against the window to dislodge unwanted material (U.S. Pat. No. 3,914,601); and an air inlet secured near the ends of optical fibers to provide air under pressure to prevent dust and debris from masking the fiber ends (U.S. Pat. No. 4,057,146).
Previous solutions to the cleaning problem, however, require a relatively large amount of air which itself may contain debris, dust, or oil. Also, an air blast may project residue or material from an object to be sorted onto a surface or window (e.g. oily residue from a peanut). In one previous attempt to clean a viewer window, a tubular ring was immovably disposed above the window, the ring having a plurality of holes around it through which air under pressure was directed through the window. It is also known in the prior art to position brushes against a viewer glass and to move the glass (not the brushes) to clean the glass.
There has long been a need for a product sorter viewer cleaning apparatus which adequately cleans substantially all of the viewing surface or rod end surface. There has long been a need for such a cleaning apparatus which cleans contactingly with means other than or in addition to air blasts. There has long been a need for such apparatuses which clean both with air and with a cleaning element that contacts the surface to be cleaned. There has long been a need for such apparatus which uses relatively little air. There has long been a need for cleaning apparatus for object sorters which continuously inhibits the deposition of unwanted material on surfaces of viewing devices themselves or on transparent surfaces (e.g. windows) interposed between the viewing device and objects to be sorted.